platform: modularize api/gui, add docs-tests-web foundation, and refresh root config

selective-vpn-api/app/egress_identity_probe_helpers.go

@@ -0,0 +1,74 @@
+package app
+
+import (
+	"encoding/json"
+	"net/netip"
+	"os"
+	"strings"
+	"time"
+
+	egressutilpkg "selective-vpn-api/app/egressutil"
+)
+
+func egressIPEndpoints() []string {
+	return egressutilpkg.IPEndpoints(os.Getenv("SVPN_EGRESS_IP_ENDPOINTS"))
+}
+
+func egressGeoEndpointsForIP(ip string) []string {
+	return egressutilpkg.GeoEndpointsForIP(os.Getenv("SVPN_EGRESS_GEO_ENDPOINTS"), ip)
+}
+
+func egressLimitEndpointsForNetns(in []string) []string {
+	maxN := envInt("SVPN_EGRESS_NETNS_MAX_ENDPOINTS", 1)
+	return egressutilpkg.LimitEndpoints(in, maxN)
+}
+
+func egressJoinErrorsCompact(errs []string) string {
+	return egressutilpkg.JoinErrorsCompact(errs)
+}
+
+func egressSingBoxSOCKSProxyURL(client TransportClient) string {
+	if client.Kind != TransportClientSingBox {
+		return ""
+	}
+	path := transportSingBoxConfigPath(client)
+	if strings.TrimSpace(path) == "" {
+		return ""
+	}
+	data, err := os.ReadFile(path)
+	if err != nil || len(data) == 0 {
+		return ""
+	}
+	var root map[string]any
+	if err := json.Unmarshal(data, &root); err != nil {
+		return ""
+	}
+	return egressutilpkg.ParseSingBoxSOCKSProxyURL(root)
+}
+
+func egressInterfaceBindAddress(iface string) string {
+	iface = strings.TrimSpace(iface)
+	if iface == "" {
+		return ""
+	}
+	stdout, _, code, err := runCommandTimeout(1500*time.Millisecond, "ip", "-4", "-o", "addr", "show", "dev", iface, "scope", "global")
+	if err != nil || code != 0 {
+		return ""
+	}
+	for _, line := range strings.Split(stdout, "\n") {
+		fields := strings.Fields(strings.TrimSpace(line))
+		for i := 0; i < len(fields); i++ {
+			if fields[i] != "inet" || i+1 >= len(fields) {
+				continue
+			}
+			ip := strings.TrimSpace(fields[i+1])
+			if slash := strings.Index(ip, "/"); slash > 0 {
+				ip = ip[:slash]
+			}
+			if addr, err := netip.ParseAddr(ip); err == nil && addr.Is4() {
+				return addr.String()
+			}
+		}
+	}
+	return ""
+}